Chevy and GMC vehicles equipped with LGH, LML, LUZ, LWN, L5P and LH7 diesel engines may exhibit excessive smoke at the tailpipe, with DTC P2002 set. This may be the result of a cracked or broken diesel particulate filter (DPF).
Vehicles include 2010-2019 Chevy Express, 2016-2019 Colorado, 2017-2019 Cruze, 2018-2019 Equinox, 2011-2019 Silverado, and 2010-2019 GMC Savana, 2016-2019 Canyon, 2011-2019 Sierra and 2018-2019 Terrain.
A properly functioning DPF should remove most if not all soot particles from the exhaust stream. The following test should be performed immediately after a regeneration because of the reduced filtration efficiency of the DPF without any soot in it.
With assistance, the engine will need to rev to wide-open-throttle (WOT) 3 consecutive times while holding a cheese cloth over the tailpipe. A failed DPF will leave excessive soot particles on the cloth. A DPF that is working properly should show no or very minimal signs of soot particles. If the DPF is found to be the cause of heavy soot particles, replace the DPF.
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